Re： Simulation result， CST vs ADS

Kindly please see my ppt

hello hafizm,
what do you want to know? ADS considers substrate as infinite where as in CST its always finite. I can see you have three ports in ADS. How you defined it? are they differential or what? It would be better if you clarify what you are simulating. Perheps a paper from which you designing the antenna. Take a ieee paper and simulate it in both. then you can get better idea.
Regards
Praful

Thank you Praful,
I just want to know why result simulated in CST and ADS differ each other.. actually I use Port type: ground reference on gnd coplanar and internal at center conductor
thanks

The two results differ simply because the use two different EM simulation techniques. ADS MoM based on 3D planar EM technique considers substrate of infinite height while the real 3D FIT EM technique is the core kernel of CST.